GridViewDeletedEventHandler Delegát

Reference

Definice

Obor názvů:: System.Web.UI.WebControls

Sestavení:: System.Web.dll

Důležité

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Představuje metodu, která zpracovává RowDeleted událost GridView ovládacího prvku.

public delegate void GridViewDeletedEventHandler(System::Object ^ sender, GridViewDeletedEventArgs ^ e);

public delegate void GridViewDeletedEventHandler(object sender, GridViewDeletedEventArgs e);

type GridViewDeletedEventHandler = delegate of obj * GridViewDeletedEventArgs -> unit

Public Delegate Sub GridViewDeletedEventHandler(sender As Object, e As GridViewDeletedEventArgs)

Parametry

sender: Object

Zdroj události

e: GridViewDeletedEventArgs

A GridViewDeletedEventArgs , který obsahuje data události.

Příklady

Následující příklad ukazuje, jak programově přidat GridViewDeletedEventHandler delegáta k RowDeleted události GridView ovládacího prvku.


<%@ Page language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
  
  void Page_Load(Object sender, EventArgs e)
  {

    // Create a new GridView control.
    GridView customersGridView = new GridView();
    
    // Set the GridView control's properties.
    customersGridView.ID = "CustomersGridView";
    customersGridView.DataSourceID = "CustomersSqlDataSource";
    customersGridView.AutoGenerateColumns = true;
    customersGridView.AutoGenerateDeleteButton = true;
    customersGridView.DataKeyNames = new String[1] { "CustomerID" };

    // Programmatically register the event-handling method
    // for the RowDeleted event of the GridView control.
    customersGridView.RowDeleted += new GridViewDeletedEventHandler(this.CustomersGridView_RowDeleted);

    // Add the GridView control to the Controls collection
    // of the PlaceHolder control.
    GridViewPlaceHolder.Controls.Add(customersGridView);
    
  }

  void CustomersGridView_RowDeleted(Object sender, GridViewDeletedEventArgs e)
  {
    
    // Display whether the delete operation succeeded.
    if(e.Exception == null)
    {
      Message.Text = "Row deleted successfully.";
    }
    else
    {
      Message.Text = "An error occurred while attempting to deleting the row.";
      e.ExceptionHandled = true;   
    }
    
  }
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewDeletedEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridViewDeletedEventHandler Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"          
        runat="server"/>
                
      <br/>
      
      <asp:placeholder id="GridViewPlaceHolder"
        runat="server"/>
            
      <!-- This example uses Microsoft SQL Server and connects  -->
      <!-- to the Northwind sample database. Use an ASP.NET     -->
      <!-- expression to retrieve the connection string value   -->
      <!-- from the Web.config file.                            -->
      <asp:sqldatasource id="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        deletecommand="Delete from Customers where CustomerID = @CustomerID"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>
      
    </form>
  </body>
</html>


<%@ Page language="VB" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
  
  Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)

    ' Create a new GridView control.
    Dim customersGridView As New GridView()
    
    ' Set the GridView control's properties.
    customersGridView.ID = "CustomersGridView"
    customersGridView.DataSourceID = "CustomersSqlDataSource"
    customersGridView.AutoGenerateColumns = True
    customersGridView.AutoGenerateDeleteButton = True
    
    Dim keyArray() As String = {"CustomerID"}
    customersGridView.DataKeyNames = keyArray

    ' Programmatically register the event-handling method
    ' for the RowDeleted event of the GridView control.
    AddHandler customersGridView.RowDeleted, AddressOf CustomersGridView_RowDeleted

    ' Add the GridView control to the Controls collection
    ' of the PlaceHolder control.
    GridViewPlaceHolder.Controls.Add(customersGridView)
    
  End Sub

  Sub CustomersGridView_RowDeleted(ByVal sender As Object, ByVal e As GridViewDeletedEventArgs)
    
    ' Display whether the delete operation succeeded.
    If e.Exception Is Nothing Then
    
      Message.Text = "Row deleted successfully."
    
    Else
          
      Message.Text = "An error occurred while attempting to deleting the row."
      e.ExceptionHandled = True
      
    End If
    
  End Sub
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewDeletedEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridViewDeletedEventHandler Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"          
        runat="server"/>
                
      <br/>
      
      <asp:placeholder id="GridViewPlaceHolder"
        runat="server"/>
            
      <!-- This example uses Microsoft SQL Server and connects  -->
      <!-- to the Northwind sample database. Use an ASP.NET     -->
      <!-- expression to retrieve the connection string value   -->
      <!-- from the Web.config file.                            -->
      <asp:sqldatasource id="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        deletecommand="Delete from Customers where CustomerID = @CustomerID"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>
      
    </form>
  </body>
</html>

Následující příklad ukazuje, jak deklarativně přidat GridViewDeletedEventHandler delegáta k RowDeleted události GridView ovládacího prvku.


<%@ Page language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  void CustomersGridView_RowDeleted(Object sender, GridViewDeletedEventArgs e)
  {
    
    // Display whether the delete operation succeeded.
    if(e.Exception == null)
    {
      Message.Text = "Row deleted successfully.";
    }
    else
    {
      Message.Text = "An error occurred while attempting to delete the row.";
      e.ExceptionHandled = true;   
    }
    
  }
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView RowDeleted Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView RowDeleted Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"          
        runat="server"/>
                
      <br/>
            
      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="true"
        autogeneratedeletebutton="true"
        datakeynames="CustomerID"
        onrowdeleted="CustomersGridView_RowDeleted"  
        runat="server">
      </asp:gridview>
            
      <!-- This example uses Microsoft SQL Server and connects  -->
      <!-- to the Northwind sample database. Use an ASP.NET     -->
      <!-- expression to retrieve the connection string value   -->
      <!-- from the Web.config file.                            -->
      <asp:sqldatasource id="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        deletecommand="Delete from Customers where CustomerID = @CustomerID"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>
      
    </form>
  </body>
</html>


<%@ Page language="VB" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  Sub CustomersGridView_RowDeleted(sender As Object, e As GridViewDeletedEventArgs)
    
    ' Display whether the delete operation succeeded.
    If e.Exception Is Nothing Then
    
      Message.Text = "Row deleted successfully."
    
    Else
          
      Message.Text = "An error occurred while attempting to delete the row."
      e.ExceptionHandled = True
      
    End If
    
  End Sub
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView RowDeleted Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView RowDeleted Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"          
        runat="server"/>
                
      <br/>

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="true"
        autogeneratedeletebutton="true"
        datakeynames="CustomerID"
        onrowdeleted="CustomersGridView_RowDeleted"  
        runat="server">
      </asp:gridview>
            
      <!-- This example uses Microsoft SQL Server and connects  -->
      <!-- to the Northwind sample database. Use an ASP.NET     -->
      <!-- expression to retrieve the connection string value   -->
      <!-- from the Web.config file.                            -->
      <asp:sqldatasource id="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        deletecommand="Delete from Customers where CustomerID = @CustomerID"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>
      
    </form>
  </body>
</html>

Poznámky

Ovládací GridView prvek vyvolá RowDeleted událost při kliknutí na tlačítko Odstranit (tlačítko s CommandName jeho vlastností nastavenou na "Delete") v rámci ovládacího prvku, ale poté GridView , co ovládací prvek odstraní záznam. To vám umožní poskytnout metodu zpracování událostí, která provádí vlastní rutinu, jako je kontrola výsledků operace odstranění, kdykoli dojde k této události.

Při vytváření delegáta GridViewDeletedEventHandler identifikujete metodu, která bude zpracovávat událost. Pokud chcete událost přidružit k obslužné rutině události, přidejte do události instanci delegáta. Obslužná rutina události je volána při každém výskytu události, dokud neodeberete delegáta. Další informace o delegátech obslužné rutiny událostí najdete v tématu Zpracování a vyvolávání událostí.

Metody rozšíření

GetMethodInfo(Delegate)

Získá objekt, který představuje metodu reprezentovanou zadaným delegátem.

Platí pro

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